Mobile communication devices are popular for business and personal use. Such devices include Personal Digital Assistants (PDA), cellular phones, mobile phones, smart phones, and computers. These mobile devices provide wireless two-way voice and data communication over wireless networks. The wireless networks may be, but are not limited to, GSM/GPRS, CDPD, TDMA, CDMA, iDEN Mobitex, DataTAC, EDGE, EV-DO, UMTS, Bluetooth, variants of 802.11, and other wireless networks.
Electromagnetic fields are generated by electronic devices. The electromagnetic fields may interfere with other nearby electronic devices. The international standards on Hearing Aid Compatibility (HAC) establish a minimum signal-to-noise ratio at the T-coil of a hearing aid for effective magnetic wireless coupling to the hearing aid, (including cochlear implants, and assistive listening devices), while minimizing magnetic interference. Traditional approaches to meet the required signal-to-noise ratio in the presence of magnetic fields generated by mobile communication devices include increasing current to the receiver in the mobile communication device, installing a separate T-coil within the mobile communication device to increase the signal, and altering current loops and circuit board traces within the mobile communication device to reduce the noise from magnetic interference.